This disclosure generally relates to a method and apparatus for wireless communications, and more particularly relates to a control channel design for many-antenna multi-user (MU) multiple-input multiple-output (MIMO) systems.
Many-antenna MU-MIIMO based communication faces a previously unaddressed challenge that it lacks a practical control channel. The potential range of MU-MIMO beamforming systems scales with up to the square of a number of antennas at a base station once the base station has channel state information (CSI). On the other hand, the range of traditional control channel operations remains constant since the control channel operations take place before or during CSI acquisition. The range gap between no-CSI and CSI modes presents a challenge to the efficiency and feasibility of many-antenna base stations.
Many-antenna MU-MIMO based communication represents a rapidly growing research field, which has recently shown promise of commercialization. However, there are still certain system challenges facing the creation of practical many-antenna base stations for many-antenna MU-MIMO wireless systems. One issue in current architectures is the lack of an efficient and reliable control channel that is required for various network operations. Wireless communication systems typically realize operations on the control channel using a single high-power antenna, or simple diversity schemes. However, these methods rapidly become very inefficient as the number of base-station antennas increases.